Seat belts are required in U.S. ambulances, as with other motor vehicles manufactured in accordance with the current Federal Motor Vehicle Safety Standards (FMVSS), as regulated by the National Highway Traffic Safety Administration (NHTSA). These regulations are also cited in the Specification for the Star of Life Ambulance, KKK-A-1822F, as issued by the General Services Administration (GSA), which is widely adopted as the defacto industry specification for ambulances. The required occupant restraints do not allow emergency medical service (EMS) workers the mobility required to care for patients.1 As a result, EMS workers routinely work unrestrained in the patient compartment, daily risking their safety and health in the care of others.2 In an effort to solve this problem for existing and new ambulances alike, the National Institute for Occupational Safety and Health tested four different retrofittable restraint systems, each of which provide improved crash protection for the worker while allowing the mobility needed to provide patient care. In parallel, the City of Winter Park (Florida) Fire and Rescue
Department (WPFD), in collaboration with Medtec Ambulance Corporation, has designed and fielded a new ambulance patient compartment that significantly reduces the need for the EMS worker to move from a seated position to care for the patient. Together, these two work environment changes represent unique opportunities to substantially improve worker safety without compromising patient care.
The objective of this research study was to utilize digital human modeling tools to evaluate reach envelopes for three different human body sizes (5th percentile female, as well as, the 50th and 95th percentile male: by stature and weight), when positioned in two different commercially available ambulance patient compartments. The evaluation was expanded to test each body size, in each environment, using two different restraint systems: one fixed and one allowing mobility, if needed, to assess the ability of a worker to care for the patient and reach equipment while remaining restrained. The underlying premise is that it is better to be restrained than unrestrained, and further, it is better to be restrained and seated than restrained and out of the seat.
Results from this study illustrate the strengths and limitations of the patient compartment configuration in an ambulance built and fielded in accordance with the current FMVSS and the Federal Specification for the Star of Life Ambulance, KKK-A-1822E, as issued by the General Services Administration (GSA). This study also discusses potential improvements to the safety and health of EMS workers, if NIOSH tested mobile restraint systems, which increase reach envelope while allowing EMS workers to remain restrained, were adopted. The approach taken by the WPFD to redesign the work environment by substantially reducing the need for mobility, thus allowing EMS workers to remain seated and restrained for the majority of their work tasks, offers a real opportunity to improve the safety of ambulances to be fielded in the future if this design were to be adopted. Finally, the WPFD design when coupled with a mobile restraint offers the best of both designs.